I don't think there is an automatic tool where you simply plug in a domain, and it will automatically scrape a URL and dump their keywords.
Your best bet would be to do this manually.
If you don't have the time or the motivation to do it, you can hire a low-cost virtual assistant to do it for you.
It won't cost much, but I suggest you don't pay a virtual assistant based on time.
If you make this mistake, they have all the incentives in the world to drag their feet.
Who wouldn't?
If you're getting paid more money for projects that take longer to complete, there is no incentive to finish things ASAP.
On the other hand, if you pay people based on results or quota, you better believe that they will try to finish as soon as possible because dragging things out doesn't make sense.
You can find quota-based virtual assistants from places like Fiverr.
You just need to contact many people and ask them if both of you can agree that you're going to pay the assistant if they complete a task within a deadline.
It's the volume part that it's going to make this arrangement tricky.
You're going to have to play the numbers game because many freelancers on Fiverr will reject you.
But some will take a quota or results-based engagement.
In Fiverr, you get the right to ask for a refund if they don't deliver the agreed-upon volume at the agreed-upon time.
There are quota-based VA platforms like Cognoplus where you don't have to bargain or play the numbers game.
They just give you a list of people who will work on a quota or results-based system.
But no matter how you cut it, get a VA to do this for you and make sure that the work is accurate.
I suggest that you first shoot the VA a video for each step, so they don't miss a crucial production step.